Small Signal Analysis of Photovoltaic based Water-Pumping System Driven by Induction Motor

Photovoltaic (PV) operated water pumping systems driven by induction motors are becoming popular in many places. The system consists of without using any storage device can make the system less expensive. However, proper energy management through an effective control technique is required to managing power balance in the system. In order to analyze the system, a small signal analysis is required to achieve the better parameters of controllers used in the system. The nonlinear model of the PV based water pumping system driven by induction motor with the help of vector controller is transferred to linear model to analyze the dynamic behavior of the system. In order to control the PV terminal voltage and speed of the motor, two PI controllers are used and designing of the parameters of the controllers is discussed in this paper through the transfer function obtained from the linear model. The response of small signal function is presented in this paper with the help of MATLAB under changing of reference dc-link voltage. Apart from this, complete mathematical analysis is included step by step for better analysis purpose.